Dr. Nick Blegen

Phone:

Email:

Main Focus

My research
focuses on understanding modern human origins through archaeological excavation
of Stone Age sites as well as the studies of volcanic glass (obsidian) and
volcanic ash layers (tephra) from the last 500,000 years in East Africa. This
work entails: 1) Establishing the geographic scale of prehistoric human
interactions via stone raw material sourcing and 2) Refining the stratigraphy
and chronology of correspondingly vast landscape-scale archaeological,
paleontological and geological deposits through correlation and dating of
volcanic ashes.

Long-distance
transport of stone materials is a feature of prehistoric human behavior that is
important for determining the geographic scale of human interactions with their
physical environments as well as with one another. Using modern digital
techniques of archaeological excavation and geochemical sourcing of obsidian
artifacts at sites from equatorial East Africa my work is showing that
prehistoric hunter-gatherer populations for the last 400,000 years before
present regularly transported obsidian distances between 55–250 km. This
behavior was not previously documented at sites dating to more than ~60,000
years ago.

To establish a
chronology of geographic scale matching the large range over which our early
modern human ancestors traversed, I combine geological survey and chemical
analysis of volcanic ashes dispersed across equatorial East Africa. Such work
has documented many widespread ash layers, some found across an area of over
115,000 km2 and correlating across several East African rift basins. All these
rift basins contain rich archaeological, fossil and paleoenvironmental
archives. These tephras thus provide the context with which to characterize
past landscapes and environments relating to human behavior and interactions on
large geographic scales commensurate with the scope of human interactions
documented by raw material sourcing.